Ryanair warns that high fuel costs will likely mean more expensive flights and frozen staff pay

Ryanair expects its fuel bill for the next financial year to cost an extra $2.4 billion. Artur Widak/NurPhoto via Getty Images

Surging fuel costs are eating into Ryanair's profits, which it has warned could lead to more expensive tickets and frozen pay for staff.

Ryanair reported on Monday that its post-tax profits were down 15% to 2.15 billion euros, or about $2.4 billion, for the six months preceding September 30.

As the world's largest budget airline , Ryanair is known for its cheap fares, bolstered by a strong fuel-hedging strategy that uses financial derivatives to lock in future prices.…